Blender 2.91 Mesh Object to 3D Print STL
Just a hunch, as I don't know anything about your slicer program. But I know people often get tripped up in other cases by joining objects without realizing the limitations of doing so. So step 7 is likely your culprit, though it may not be the only issue. I'm just betting it's one of them. When joining objects in Blender, they are almost more &quot;grouped&quot; than &quot;fused&quot;; they can be separated later. My gut tells me that your slicer program is complaining about them being joined. You will likely need to separate the joined objects and combine them properly afterwards with a boolean union operation.